


Heightened Senses

by nhasablog



Category: Spider-Man: Homecoming (2017), The Avengers (Marvel Movies), The Avengers (Marvel) - All Media Types
Genre: Fluff, Gen, Precious Peter Parker, Spidey Senses, Tickling
Language: English
Status: Completed
Published: 2018-05-07
Updated: 2018-06-07
Packaged: 2019-05-03 16:00:41
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 4,537
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14572521
Author URL: https://archiveofourown.org/users/nhasablog/pseuds/nhasablog
Summary: Tony and Peter are researching how Peter’s heightened senses are affecting him in different ways, such as his eyesight, hearing and sensitivity.





	1. Peter

**Author's Note:**

> This takes place after Infinity War, but I don’t spoil anything and basically have made up my own ending to IW part 2, where they’re all happy and living in the Avengers Tower again. I hope you like it!

Tony wasn’t sure why he hadn’t thought about it before, but apparently it had taken a boring ass meeting at 8 in the morning for his mind to even approach that territory, and after that it was the only thing he could think of.

And it was a weird thing to be thinking of.

“Do you know anything about heightened senses?” he asked Bruce once he was back at the Tower, having forgotten what the meeting had even been about.

Bruce was in the middle of buttering some toast, some freshly cut avocado on his plate. Breakfast for someone who hadn’t been forced to get up before the crack of dawn (aka 7AM in the winter in New York City). “Sorry?”

“Heightened senses. Have you ever observed the phenomenon, or at least mulled over the concept?”

“I can’t say I have, except maybe when I met Steve the first time.”

Tony let out a breath. “Oh, right, Steve! I forgot the serum gave that effect.”

Bruce raised an eyebrow. “If you weren’t thinking about Steve, then whom were you thinking of?”

* * *

 

Peter arrived straight after school to check out some upgrades Tony had done to his suit, looking cheery with his backpack still on. The epitome of youth, even though he was 18 at this point and close to graduating. Tony reckoned 18 was still young, only most people carried themselves differently in a desperate attempt to seem older. Peter still walked as if he were 15.

Tony grinned, unable to help himself. “Good day?”

Peter nodded almost eagerly. “I had, like, no classes today. Only study hall, when it turned out that half the day would be a free period, and it wasn’t actually as bad as you’d think, because it wasn’t a  _real_ study hall. Not really. We didn’t even have a teacher most of the time, so instead of having an intense day I ended up having fun. Can you believe it?” He shrugged his bag off and settled it on the floor. “And I got the majority of my homework done, too.”

“Sounds like you had a blast, which is good, because I want you to help me with something.”

Peter’s eyebrows met his hairline. “Me? To help you?”

“If you’re up for it.”

“Of course, Mr Stark!” The kid hadn’t shaken the habit of calling him Mr Stark, even though he usually only kept it up at the beginning of their meetings. “Whatever you need.”

“I had a theory.”

“Oh?”

“Well, not really a theory. I know for a fact that it’s true, but I don’t know to what extent.”

Peter didn’t say anything this time, only waited for him to continue.

Tony pointed at him. “Your Spidey senses. You’re not alone with having them.”

“Sorry?”

“I’m talking about heightened senses. There are other people with them, but we don’t know too much about them as a concept. We only know that the spider that bit you gave you the ability to feel things a normal person can’t, and we know that the serum they gave Steve is making him see and hear better, but I feel like we’ve completely overlooked how much more there probably is.”

“Mr Stark?”

“I want to compile what heightened senses mean for you, and how that differs to Steve. Start a bit of a scientific research, if you may. But only if you let me.”

Peter didn’t even hesitate. “Of course I’ll let you. I think this is really important.”

Tony’s lips twitched upward at his toned down excitement. “Oh, good. Do you have time to start now?”

“Well, I did finish a bunch of homework already.”

So that was how they ended up in Tony’s lab until way past dinner time, way past the time Peter should’ve been home, and eventually past his bedtime, though not by much. Tony sent the kid - because he was still a kid, dammit - to the room he’d set up for him years ago and spent another two hours in the lab, looking over the notes so far.

They’d examined his eyesight, hearing, even how his taste differed, and the notes were already several pages long. Some would say this whole process was unnecessary. Why should they even care about this? But to Tony it mattered, and it was a nice way to spend time with the kid.

Maybe that had been the whole point of this, deep down. Maybe not, but it was a nice bonus.

He only went to bed when Steve came and dragged him out of the lab, and Tony knew he would repeat the same process on Steve once he was done with Peter, but Steve said he didn’t mind when he brought it up.

Tony was so grateful that it was Saturday the next day, and he was grateful for his morning meeting the previous day, which had caused him to sleep in a little bit, thus reducing the time he would have to wait for Peter to wake up. God knew that kid could sleep.

Peter stumbled into the kitchen at 11, bleary eyed and not entirely in control of his limbs yet.

“Let me guess,” Tony said as Peter grabbed a cup. “You could’ve slept for at least another two hours.”

Peter barked out a laugh. “You know me so well, Mr Stark.”

“We made omelettes earlier,” Steve said, his shoulder bumping into Tony’s. “We saved you some in the fridge.”

Tony remembered an instance not too long ago when Clint had said that he and Steve were like Peter’s dads or something, and while Tony had rolled his eyes at it he knew why Clint had said it. Ever since the whole Thanos thing, when they’d saved the universe and gotten their shit together and Steve and Tony had confessed their feelings, it hadn’t taken them long to skip past the honeymoon phase and settle into a domestic bliss. Once Steve and Peter actually got to know each other they became as good friends as ever, even though Peter called him Mr Rogers, which was weird.

Tony watched Peter eat his breakfast, and then watched Steve who was watching Peter eating his breakfast, and he felt happy. For a while, he hadn’t thought it possible.

“You ready to continue our research?” Tony asked as Peter shoveled the last of his omelette into his mouth.

“Always,” he said, already his energetic self. Tony envied the young.

He clapped once. “Right! Steve, don’t wait up.”

“If you think I won’t show up in three hours to force you to have lunch you’re wrong.”

“Four hours.”

“Fine. Be careful.”

Tony rolled his eyes fondly. “We’re only examining his senses. Nothing dangerous about that.”

“You never know.”

“Fair enough.” Tony kissed him quickly, and then once more before they were off. This rainy Saturday was going to be a productive one.

* * *

 

“Is this going to hurt?”

Tony waved a hand at him. “Of course not.” Though he wasn’t actually too sure. So far they hadn’t tested how Peter’s heightened senses affected his skin, and Tony was hovering a small stick over Peter’s arm. “We’re only going to see how sensitive you are. If you bruise easily, which I don’t think you do, otherwise you’d always be black and blue.”

Peter let out a quiet laugh. “Go on, then. For science.”

Tony snorted. “That’s the spirit.”

The stick was a little pointy, but not sharp enough to pierce skin. Peter didn’t do anything in particular when Tony pressed it lightly against his arm. Only watched it intently until Tony removed it, and they both observed the tiny mark it had left which was quickly disappearing.

“Interesting,” Tony said. “This is good. The heightened senses don’t cause you to injure more easily.”

“That could barely have injured me, though.”

“Still. This is good.” He paused, still holding the stick. “Maybe we should try more spots.”

Peter agreed and Tony prodded his shoulder, back, thigh, even his face, which was kind of hilariously uncomfortable for them both. Tony was so in the zone that he saw nothing wrong with asking Peter to lift his shirt a bit so that he could try out his ribs to “make sure it’s not easy to break them”.

He did notice Peter flinching when he poked him, though.

“Oh, shit, we’ve found a malfunction, we-” He cut himself off when Peter grinned sheepishly at him. “What?”

“It, well, I don’t think that was the heightened senses.”

“What do you mean?”

“I mean it tickled, and I was ticklish beforehand.”

“Oh. Right, of course- wait a minute.” Tony literally facepalmed. “It might not affect your pain threshold, but I bet it affects your sensitivity to lighter touch.” He turned to Peter. “I’ll need to tickle you.”

“Sorry?” Peter spluttered out, face reddening. “Is that really necessary?”

“I’m not gonna, like, do it for  _ages_. Just wanna check a couple of different spots. Tell me.” Tony poked him in the arm with the stick. “How ticklish were you before? And where?”

“I, uh, well-” Peter laughed, nervous and timid and making Tony realize why parents loved embarrassing their kids. He tried to keep a straight face as Peter stumbled over his words. “I guess I was pretty ticklish beforehand, mostly in the usual places.”

“Was there a place you  _weren’t_ ticklish?”

“My shoulders maybe?”

“Is that all?”

“Possibly shoulder blades?”

“Possibly?”

“No one really tried to tickle me there.”

Tony couldn’t help his grin now. “Right. So we’ll try out a few spots and compare them, okay?”

“Are you still gonna use the stick?”

“I can try, but I have a feeling my hands might be more effective, unfortunately.” Oh, Tony couldn’t wait to try this out on Steve when it was his turn.

He started by running the tip of the stick lightly over Peter’s shoulder, shoulder blades and ribs, and while he twitched a bit when he went for the rib area, Tony could tell the stick wasn’t working. He put it aside and repeated his actions using his fingertips, and he wouldn’t be able to conceal his mirth when Peter laughed even if he’d wanted to.

“Okay, so ribs are definitely ticklish. Your shoulders seem good, but you seemed to tense up a bit when I went for your shoulder blades.” Tony had given Peter the task of writing this down, and he took advantage of him being occupied and gave his right shoulder blade a poke with his finger.

Peter jerked away with a gasp and turned to Tony with wide eyes. “Shoulder blades are ticklish,” Tony confirmed, and Peter wrote it down wordlessly.

“I wish I could’ve tried this out before you were Spiderman,” Tony said a while later, after they’d tried out several spots that all proved to be rather sensitive. “It’d be easier to determine whether you’re indeed more ticklish now than before.”

“I think I am,” Peter said, having long ago stopped averting his gaze in embarrassment (though his face was perpetually flushed). “I mean, I can’t remember ever having squealed when someone squeezed my sides before.”

“That was kind of funny,” Tony said, and Peter laughed. “Hopefully no enemies will get a hold of this info.”

“We should burn the notes.”

Tony nodded. “Before someone tickle tortures you during an interrogation.”

Peter shuddered. “That’d be awful.”

Tony grinned, his hand finding Peter’s ribs automatically now. It was like his second nature to poke the kid at this point. “You think you’d crack?”

“I’d rather not find out.”

Tony thought of how fun it could be to have a tickle fight with someone. How fun and nice and safe. “Do you hate it?”

“Being tickled?”

“Uh huh.”

“Not really. Do you? Are you even ticklish?”

Tony could feel his own face heating up now, which Peter no doubt saw and started grinning about. “I, uh, it can be fun. And yes, I am, but don’t you dare, kid. I’m not the subject here.”

“I wouldn’t even dream of it.”

“Now lift your shirt again so that I can try your stomach.”

Conclusion: the belly was Spiderman’s most ticklish spot.


	2. Tony

**Summary for the Chapter:**

> Steve walks in on Tony “researching” and decides to help out, but not in Tony’s favor.

**Notes for the Chapter:**

> So this turned into a mini series. Whoops?

Tony hadn’t expected Steve to walk in to drag them to lunch just as he was tickling Peter’s knees, the kid nearly falling out of his seat as Tony kept claiming he couldn’t let go just yet for reasons he didn’t elaborate on. He wasn’t sure which one of them was more embarrassed when Steve raised an amused eyebrow at them, but Tony had to admit that he felt a bit sheepish, if only for a moment.

“The Spidey thing makes him more sensitive,” he explained as Peter tried to catch his breath. “I’ve spent the past half hour tickling him for science, if you can believe it.”

“Science, huh?” Steve entered the room fully, the smirk on his lips the first sign of trouble. “I feel like it’s my duty to tell him about your sweet spot on your lower stomach.”

Tony glared at his boyfriend. “Wow. Traitor. I want a divorce.”

“You guys are married?” Peter asked, his voice still a bit higher than usual.

“No, but I want a divorce anyway.”

Steve barked out a laugh. “All because I told Pete you’re ticklish?”

“He was already aware of it.” Tony pointed between them. “We have good communication in this partnership.”

“Is that so?”

“Uh huh.”

“How much did he blush while telling you?” Steve asked Peter, who was feeling stable enough again to grin.

“I could see his face reddening a bit,” he said, shooting Tony an amused look. Wow, okay, so this is how it was now?

Tony crossed his arms. “You’re next, Rogers. I told you I was gonna repeat the whole process on you.”

“Yeah, well, I think maybe we need to compare how someone without heightened senses reacts to it in order to have complete data, don’t you think, Peter?”

Peter was nodding. “I think that’d be a great idea, Mr Rogers.”

“No, no, wait a minute.” Tony held up his hands, palms up, a helpless smile growing on his lips. “This really isn’t necessary for the research.”

“Nothing is unnecessary when it comes to research,” Peter said. “You of all people should know that, Mr Stark.”

And then, before he could really process it all, Tony had been trapped between their bodies and a wall, and Steve, who had reduced him to a giggly mess many times before, wasted no time at all. Tony was laughing within seconds.

“See, Peter,” Steve was saying as his fingers worked their way between Tony’s flailing arms to prod at his upper body. “I’m sure that if Tony would get bitten by something and somehow get heightened senses himself, he would die the moment someone touched him. I mean.” His fingertips skimmed Tony’s neck, making him scrunch up his shoulders with a small shriek. “If this is how he reacts  _now_.”

“Don’t be mean!” Tony managed to choke out. Peter was so far only watching Steve demolish him, but it was a bit embarrassing anyway.

“I’m not mean,” Steve protested. “I’m just adding to the research.”

Tony grabbed one of his wrists, and while he knew that Steve could writhe free easily he allowed himself to be captured. “Stop.”

“Can’t handle it?”

“Steve, we- we’re not  _alone_.”

“So? Peter doesn’t mind.”

“I don’t,” Peter confirmed, visibly biting back the intensity of his smile now.

“In fact, he’d like to contribute, wouldn’t you?”

“Oh, uh…”

“Don’t pressure him,” Tony said, partly for his own sake and partly for Peter’s.

“No, no, he’s not pressuring me,” Peter assured them. “I just- I have a feeling Mr Stark won’t let me live it down if I help.”

“Got that right, kid.”

“But Mr Stark has a boyfriend ten times as strong as him.” Steve winked at Tony. “I’ll handle him if he becomes difficult.”

And that was how Peter Parker reached out to tickle Tony Stark. It was brief, the movements hesitant, but it happened. Quick pokes to Tony’s ribs while Steve turned the tables and was now holding onto  _Tony’s_ wrists in order to give Peter better access. The kid made him giggle easily. It was embarrassing, but somehow Tony didn’t mind too much. They’d reached that stage, he decided.

“Mercy,” he said, letting go of his dignity entirely and sliding down the wall to try to curl up on the floor. Steve followed him, but Peter backed off with a laugh. “You doing all right, Mr Stark?”

“You better run,” was all Tony said, but the smile on his face dampened his attempt at a threat.

Peter crossed his arms. “You can’t tell me you wouldn’t have taken advantage of this for the rest of your life anyway.”

Tony snorted. “You got me there. Honey, help me up, will you?”

Steve hauled him to his feet. “All right, no more messing around. I’m sorry, researching.”

“Wow. Low blow.”

“Lunch time. Come on.”

Tony prodded at Peter’s shoulder blade as he walked past him, making him quicken his pace. “Yeah, good idea.”

Later, when they were back in the lab to conclude their research, Peter snuck a few pokes to Tony’s sides, which of course resulted in Tony doing the same to him, and all in all it was a very giggly end to a rather giggly day.


	3. Steve

**Summary for the Chapter:**

> It’s finally time to continue their research on Steve. To say that Tony is excited is an understatement.

**Notes for the Chapter:**

> Final part! Hope you like it!

Peter stayed another night, but only after Tony promised May over the phone that he’d return him the next day.

“I wouldn’t dream of keeping him from his loving aunt,” he said, and he could tell May was rolling her eyes on the other line.

Peter spent Sunday morning finishing up his homework in the kitchen while Tony joined Steve in the gym purely so that Steve would pretend he couldn’t kick his ass.

“Is it strange to you?” Steve asked as he dodged one of Tony’s high kicks.

Tony groaned, one hand pushing his hair out of his eyes. “What is?”

“That Peter is just- well, here. That we’re all sort of living our own lives instead of catering to him every second.”

“He’s not a guest. You weren’t around for the majority of this development, but situations like these aren’t necessarily rare.”

“I see.” Steve managed to punch his shoulder, though the force was so nonexistent it might as well not have happened. “Don’t get me wrong. This isn’t me criticizing the scenario. I actually really like that he’s here.”

“Good, because things would be very awkward if you didn’t.”

Steve laughed and Tony took the opportunity to hit him in the chest.

“For real though,” Tony said later as they were walking back to their room to shower. “You like him, right?”

“Peter?”

“Him.”

“Of course.” Steve raised an eyebrow at him. “You think I’m just pretending?”

“No, no, but like. I wouldn’t peg you as the type to be rude to a kid even if you didn’t like him.”

“He’s very likable.”

“ _That_ he is.”

“Were you worried we wouldn’t get along?”

“Sort of? I mean, the first time I met him it was to recruit him to a fight against you.”

“You had hoped there would be no fight, though.”

“True but- I guess he’s just not been around when things between us were good.”

“He’s around now. It’s been over a year since we reconciled.”

It had taken them a while to be able to talk about this without things getting awkward, but Tony was glad that they’d reached that point.

They approached the elevator and Tony pressed the button before saying, “That’s true. I guess I was a bit worried Pete would be the type to hold grudges.”

He left out any mention of how hurt he’d been after Steve had left with Bucky and the others. How he’d walked around with so much resentment for so long that any mention of dear old Captain America left him practically defenceless against his own emotions. He would be a fool to think Peter hadn’t noticed.

Steve reached for his hand when they stepped into the elevator, his movements so visibly hesitant that Tony almost felt bad for having brought this up, but he took it and squeezed it without any preamble.

Peter was sitting in a sea of books when they entered the kitchen a while later, every inch of the table practically covered with the kid’s homework. He glanced up to greet them, but Tony could tell his mind had been so occupied he’d practically forgotten where he was.

“I  thought you said you had already done a bunch of your work on Friday,” Tony said as Steve handed him a cup.

Peter blinked. “I had.”

Tony pointed to the table. “That looks like a lot.”

“Mr Stark, I’m a senior.”

Maybe it was because Tony had skipped so many grades and entered college early that he thought high school kids had it easy. Maybe things had changed since Tony had been in school. Or maybe he’d just forgotten that Peter wasn’t a sophomore anymore.

“Oh. Right.” He poured himself some coffee. “How’s it going then?”

“It’s going well. I’m almost done.”

“Good boy. Then you can help me start the research about Steve.” He shot his boyfriend a grin when he groaned.

“Do we have to?”

“Of course, babe. You said you didn’t mind. And besides.” He sat down across from Peter and placed his cup on an empty spot on the table. “After yesterday I think I deserve some revenge.”

Steve snorted. “As if I couldn’t wreck you within seconds.”

“Peter would help me. Wouldn’t you, Pete?”

Peter held up his hands. “I don’t want to get involved.”

“You got involved the moment you followed Steve’s instructions yesterday, kiddo.” Tony took a sip. “But it’s okay! I forgive you as long as you’re willing to follow me as blindly.”

“That’s manipulation, Tony,” Steve said, finally sitting down beside him.

“You gotta work with what you have.”

“Whatever. Peter, you’ve eaten?”

* * *

 

Peter was with them when they started the research, and Tony was being very thorough with it, partly so that Steve wouldn’t accuse him of being mean, partly because he really did want to try out everything he’d done with Peter as well. This stuff was  _interesting_ , and he couldn’t believe he hadn’t tried to figure it out beforehand.

“We’re nearing the sensitivity part,” he said, scribbling something down on a piece of paper (even though Peter was taking notes for him). “You ready?”

Steve was shaking his head. “You’re really gonna check every single spot?”

“Of course! We did that on Pete, didn’t we?”

“We did,” Peter said, and Tony could tell the kid’s amusement almost matched his own.

“But you already know my worst spots,” Steve protested.

“So? You knew mine before yesterday.”

“Wow. I can see why you wanted to divorce me.”

Peter was giggling as Tony completed checking out Steve’s eyesight, but it was nothing compared to the laugh of delight Tony let out once he was done. “Right! Tickle time.”

Steve groaned. “Please be quick.”

“Quick? While researching? Not gonna happen, babe.”

Tony adored the hint of a smile on Steve’s lips. Barely a shadow, but managing to light up his eyes anyway. If Peter wasn’t here Tony would’ve kissed that smile fully into existence, but he had manners after all.

“Pete, you wanna help?”

Peter straightened. “How, sir?”

“Well, I wouldn’t want Mr super soldier to knock me into the wall-”

“I would never-”

“-so how about you try to hold him back if he attempts it? Or at least keep an eye on his arms.”

“Will do.”

“Good, good. You ready, honey?”

“Just get it over with.”

“Testy.”

Tony knew Steve wasn’t actually as annoyed about this as he pretended to. It was mostly an act, one Tony himself replicated whenever he was in Steve’s shoes. It was just easier that way.

He rubbed his hands together. “I want to start with your hands and arms like we did with Pete. Also because I’m sure it won’t tickle enough for you to want to kill me.”

“Tony-”

“Three, two, one, go.”

Steve tried to pull his hand back automatically, but relaxed once he realized what was going on. Tony trailed his fingertips lightly over his palm, watching Steve intently for his reaction. He merely grinned, but it didn’t seem to tickle enough to get him to laugh.

The closer he got to his torso, the more sensitive Steve seemed to be. Tony traced the skin of his arm and shoulders, skipping his neck for now to go for his shoulder blades and back, which made him squirm, but not enough to make him giggle.

“You two seem to be just as sensitive so far,” Tony said. “Pete, can you write that down?”

Peter stopped observing Steve and did as he was told. Tony sent Steve a smirk while the kid had his back turned; one Steve returned easily. Tony knew what that meant. It was a promise for revenge later on. He didn’t fully mind, though he would protest the entire time.

“I’m excited about this part,” he said. “You haven’t lived until you’ve witnessed Captain America giggle as you tickle his upper body.”

Peter barked out a laugh. “Better be careful, Mr Stark.”

“Was that a threat?”

“It was me reminding you that Mr Rogers is a lot more capable of keeping you pinned.”

Tony snorted. “As if I wasn’t aware of it. That’s why this is so much fun.” Tony poked Steve’s chest. “You ready, honey?”

Steve sighed. “As ready as ever. I’ll remember how you dragged this out by the way.”

“Oh hush and let me make you laugh.”

Laugh he did. More hysterically than either of them had probably expected. While Peter’s giggling was nervous, Steve’s was more booming, though Tony wouldn’t blame that on him being more sensitive per se. He was more used to this; to Tony reducing him to an incoherent mess. He had accepted his fate, unlike Peter who had tried to remain composed.

“Stop squirming, I’m trying to get your lowers ribs.”

Steve didn’t reply, but Tony knew he would roll his eyes if he could.

“Pete, are you writing this all down?”

“Yes, sir.”

“Any theories about who’s more sensitive?”

“Uh, not really.”

“We’ll figure it out later. Steve, be still.”

“Stop!”

“Nah.”

And the day dragged ever on.

* * *

 

“Who do you think would win in a tickle fight between the two of you?”

The research was finished and Steve was catching his breath while Tony and Peter tried to make sense of their notes. The question had lingered in Tony’s mind since the previous day.

“I’m not sure,” Steve said. “We both seem to be quite strong, so I guess it would all depend on who managed to get the other one pinned first.”

Peter crossed his arms. “I’d rather not find out.”

Steve and Tony barked out a laugh so similar it was almost creepy. “Don’t worry, kiddo. The only person I’ll tickle is Tony.”

“Hey.”

“Later.”

Tony pointed at him. “That’s a threat.”

“It’s a promise.”

“I’m kind of happy I’m going back home later.”

It had been a rather successful weekend, if Tony did say so himself.

**Author's Note:**

> Here's my [tumblr](http://nhasablog.tumblr.com).


End file.
